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Biomedical subjects

D Sarkar

Publications and source records attributed to D Sarkar.

At least 109 records · Page 6Linked to original sources
PubMed1976

Sialic acid and sialidase activity in human endometrial tissue, uterine fluid and plasma under different conditions of uterine dysfunction.

Sialic acid content in endometrial tissue and sialidase activity in the endometrium, uterine fluid and plasma has been measured in normal and in conditions of uterine dysfunctions. It has been observed that an antagonistic effect exists between endometrial sialidase and sialic acid content, but in all the cases of uterine dysfunctions, the sialidase activity in uterine fluid and plasma decreases, whereas it increases during pregnancy.

Adult↗
PubMed1976

Direct spectrofluorophotometric determination of porphyrin in diluted urine.

Direct dilution of freshly passed urine with 19 to 99 volumes of an acid-alcohol solution of chloranil (2, 3, 5, 6-tetrachloro-1, 4-benzoquinone) results in rapid and apparently quantitative conversion of porphyrinogen to fluorescing porphyrin. Dilution must be sufficient to yield an essentially colorless solution. Under these conditions, excitation of fluorescence by 401--405 nm light and fluorescence analysis at 652 nm results in almost complete elimination of quenching and of non-specific fluorescence under the conditions described. Fluorescence intensity is relatively stable for up to several weeks. Alternatively, urine is added to NaHCO3 to permit quantitative conversion of porphyrinogen to porphyrin in 1 to 2 days, and assayed similarly following dilution with the same acid-alcohol diluent (with or without chloranil) or with dilute HCl solution alone. Quantitative results are shown to agree well with those obtained following purification by other, more tedious, procedures. The method has been tested successfully with urines from humans, cows, and rats.

Bicarbonates↗
PubMed1976

Chromatography on Florisil in the quantitative estimation of urinary and other porphyrins.

We describe the use of Florisil chromatography to purify and fractionate porphyrins into uro-, copro-, and protoporphyrins before their measurement by quantitative fluorometry. Porphyrinogens in fresh urine may be rapidly oxidized to porphyrins by chloranil, or slowly in weakly alkaline solution, before the sample is applied to the Florisil column. Aliquots of the separate ammoniacal eluates may be lyophilized for additional fractionation by direct thin-layer chromatographic analysis if desired. The behavior of delta-aminolevulinic acid, porphobilinogen, and other pyrrole compounds in this system is also described.

Chromatography↗